Plug-in type christmas tree light



, May 4, 1965 J. M. AHRONl ETAL 3,182,135

PLUG-IN TYPE CHRISTMAS TREE LIGHT Filed Feb. 21, 1963 FIG.I

IN VENTORS JOSEPH M. AHRONI LEE. AHRONI V-KL'VIA} ATTORNEYS United States Patent 3,182,185 PLUG-IN TYPE CHRISTMAS TREE LIGHT Joseph M. Ahroni and Lee Ahroni, both of R0. Box 3907, Seattle, Wash. Filed Feb. 21, 1963, Ser. No. 260,152 2 Claims. (Cl. 240-) The present invention relates to incandescent lights for decorating Christmas trees and other festive objects, and more particularly to an improved plug-in type lamp and socket assembly therefor.

Important objects of the invention are to provide such an assembly which is of simple and economical construction, andin which the lamp can be easily inserted into and removed from the socket when desired, but in which the lamp will not disengage from electrical connection with its socket while in storage or use due to jarring or vibration as has been the difiiculty commonly experienced with Christmas tree lights in the past.

Other more particular objects and advantages of the invention will, with the foregoing, appear and be understood in the course of the following decription and claims, the invention consisting in the novel construction and in the adaptation and combination of parts hereinafter described and claimed.

In the accompanying drawings:

FIG. 1 is an elevational view of an assembled lamp and socket unit embodying the present invention.

FIG. 2 is an exploded elevational view of the lamp and socket components.

FIG. 3 is an elevational view, partly in vertical section, of the lamp component.

FIG. 4 is a transverse sectional view taken along the line 4-4 of FIG. 1.

FIG. 5 is an enlarged top plan view of the socket component; and

FIG. 6 is an enlarged bottom plan view of the socket component before insertion of the ferrule and power leads.

Referring to the drawings it is seen that the incandescent electric lamp and socket of the present invention are designated 10 and 11, respectively, and that the insulated power leads to the latter numbered 12-12. A Christmas tree lighting set comprises a string of these sockets wired in series with a conventional plug for a wall socket. The set may be provided with a movable sleeve 13 adjacent each socket 11 whereby the socket can be positioned on a tree branch by inserting the branch between the leads 12 and between the sleeve and the socket, and then sliding the sleeve toward the socket to clamp the branch therebetween.

The lamp 10 comprises a plug unit 14 and an incandescent bulb 15 of the wire-base type wherein the spaced filament leads 16-16 project from the base of the bulb. Both the plug 14 and socket 11 are molded from polypropylene or some other suitable electrically nonconductive material. The main body 17 of the plug is cylindrical and has an annular stop flange 18 at the top rimming the mouth of a cavity 20 in which the base of the bulb 15 is seated and secured by a suitable adhesive 19. A pair of diametrically-spaced prongs 21-21 depend in parallel relation from the base of the plug. Each of these prongs has a longitudinal through-bore 23 opening at the top to the cavity 20 and has one of the filament leads 16 threaded therethrough. The free end portion of each filament lead extends beyond the related prong and when the plug is installed, this free end portion is doubled back over the lower end and outer face thereof as shown in FIG. 2.

Continuing to the socket 11, it is seen that such has an enlarged headsection 24 at the top of a cylindrical 3,182,185 Fatented May 4, 1965 base section 25. The head section 24 is internally formed with the principal socket cavity 26 to receive the main body 17 of the plug while the base section 25 has a pair of longitudinal through-bores 27-27 extending from the floor of the cavity 26 to the bottom end of the socket. These socket bores 27 are positioned to register with the prongs 21, but are slightly larger in diameter to receive brass ferrule terminals 28-28 which are spaced from the lower end of the socket. The end portions of the power leads 12 are threaded with their insulation 12a through the base of the socket and have their terminal end portions bared of insulation and projected into the lower ends of the ferrules 30. Preferably the insulation 12a butts against the lower end of the ferrules while the bared end portions of the leads are secured in the ferrules as by solder beads.

Assembly of the socket 10 may be performed by threading the leads 12 completely through the bores 27 and cavity 26, and then, after stripping the insulation from a short terminal portion of the leads either before or after the threading step, applying the ferrules 28. This is accomplished by dropping a bead of solder onto the bared end of each lead and then sleeving the ferrules thereover until they engage the insulation. When the solder has set the leads 12 are pulled back through the socket until the ferrules are completely seated by a snug fit in the bores 27.

The prongs 21 are slightly smaller in external diameter than the internal diameter of the ferrules 28 to accommodate the thickness of the filament leads 16. Thus when the lamp 1%) is plugged into the socket 11 with the prongs 21 projecting into the ferrules 28 and the stop flange 18 seated against the upper end of the socket, the terminal portions of the filament leads are pressed or wedged between the prongs and the inner face of the ferrules thereby completing the electrical circuit from the power leads to the lamp filament. This is true regardless of which part of the outer face of the prongs is engaged by the doubled-back portions of the filament leads 16. The lamp can be easily manually pulled from the socket for replacement or color rearrangement by gripping the socket in one hand, and with the other hand, either directly gripping the bulb 15 or wedging the nails of the thumb and fore-finger beneath the stop flange 18 to grip the latter. Yet, jarring or vibration of the lamp while in storage or use, will not loosen the lamp from its socket.

It is believed that the invention will have been clearly understood from the foregoing detailed description of my now-preferred illustrated embodiment. Changes in the details of construction may be resorted to without departing from the spirit of the invention and it is accordingly my intention that no limitations be implied and that the hereto annexed claims be given the broadest interpretation to which the employed language fairly admits.

What we claim is:

1. A light comprising an electrically nonconductive socket member having an upper exposed socket cavity intersected at the bottom by a pair of longitudinal through bores extending to the base of the socket member, electrically conductive ferrules in said bores, electrically insulated power leads extending upwardly into said bores and having their ends bared of insulation and connected to the lower ends of said ferrules, an electrically nonconductive plug member having a body portion seated in said socket cavity and an integral pair of hollow electrically non-conductive prongs projecting downwardly from said body portion into said ferrules, and an upwardly projecting incandescent bulb fixedly seated in said body portion of the plug member and having a pair of filament leads extending downwardly therefrom through said prongs, the free end portions of said filament leads Q7 being doubled back over the bottom of said prongs and pressed between said prongs and ferrules.

2. A light comprising an electrically non-conductive socket member having an upwardly exposed pair of bores extending to the base thereof, electrically conductive ferrules in said bores, electrically insulated power leads extending upwardly into said bores and having their ends bared of insulation and connected to said ferrules, an electrically non-conductive plug member having a pair of hollow electrically non-conductive prongs projecting downwardly into said ferrules, and an upwardly projecting incandescent bulb fixedly seated in said plug member and having a pair of filament leads extending downwardly therefrom through said prongs, the free end portions of said filament leads being doubled back over the bottom of said prongs and pressed between said prongs and ferrules.

References Cited by the Examiner UNITED STATES PATENTS NORTON ANSHER, Primary Examiner.

UNITED STATES PATENT OFFICE Certificate Patent No. 3,182,185 Patented May 4, 1965 Joseph M. Ahroni and Lee Ahroni Application having been made jointly by Joseph M. Ahroni and Lee Ahroni, the inventors named in the patent above identified; and Riken Shinku Kogyo Kabushiki Kaisha, Tokyo, Japan, a corporation of Japan, the assignee, for the issuance of a certificate under the provisions of Title 35 Section 256 of the United States Code, deleting the name of the said Lee Ahroni from the patent as a joint inventor, and a showing and proof of facts satisfying the requirements of the said section having been submitted, it is this 7th day of J une 1966, certified that the name of the said Lee Ahroni is hereby deleted from the said patent as a joint inventor with the said Joseph EDWIN L. REYNOLDS, First Assistant Gammz'ssz'aner of Patents. 

1. A LIGHT COMPRISING AN ELECTRICALLY NONCONDUCTIVE SOCKET MEMBER HAVING AN UPPER EXPOSED SOCKET CAVITY INTERSECTED AT THE BOTTOM BY A PAIR OF LONGITUDINAL THROUGH BORES EXTENDING TO THE BASE OF THE SOCKET MEMBER, ELECTRICALLY CONDUTIVE FERRULES IN SAID BORES, ELECTRICALLY INSULATED POWER LEADS EXTENDING UPWARDLY INTO SAID BORES AND HAVING THEIR ENDS BARED OF INSULATION AND CONNECTED TO THE LOWER ENDS OF SAID FERRULES, AN ELECTRICALLY NONCONDUCTIVE PLUG MEMBER HAVING A BODY PORTION SEATED IN SAID SOCKET CAVITY AND AN INTEGRAL PAIR OF HOLLOW ELECTRICALLY NON-CONDUCTIVE PRONGS PROJECTING DOWNWARDLY FROM SAID BODY PORTION INTO SAID F ERRULES, AND AN UPWARDLY PROJECTING INCANDESCENT BULB FIXEDLY SEATED IN SAID BODY PORTION OF THE PLUG MEMBER AND HAVING A PAIR OF FILAMENT LEADS EXTENDING DOWNWARDLY THEREFROM THROUGH SAID PRONGS, THE FREE END PORTIONS OF SAID FILAMENT LEADS BEING DOUBLED BACK OVER THE BOTTOM OF SAID PRONGS AND PRESSED BETWEEN SAID PRONGS AND FERRULES. 